Tool for marking circumferentially spaced holes



W. R KAECK July 29, 1969 TOOL FOR MARKING GIRCUMFERENTIALLY SPACED HOLES Filed May 5. 1967 wlllmor $632k A TORNEYS United States Patent 3,457,651 TOOL FOR MARKING CIRCUMFERENTIALLY SPACED HOLES Willmot Richard Kaeck, 1867 Bandoni Ave., San Lorenzo, Calif. 94580 Filed May 3, 1967, Ser. No. 635,785 Int. Cl. B2511 7/00; B25d /00 US. Cl. 33189 5 Claims ABSTRACT OF THE DISCLOSURE A marking tool for locating bolt circles in which a pair of arms are pivotally connected together at a common center. Each arm carries a punch which is movable along the length of its respective arm and which may be secured in position on its arm at a preselected distance from the common center pivot.

Background of the invention This invention generally relates to devices for producing punch marks or similar indicia on a work piece. In many instances, it is necessary in connection with the laying out of circumferentially positioned bolt holes or the like .to provide suitable punch marks on the work piece at varying circumferential spacing relative to each other as well as at varying radial spacing relative to a common center. Such punch marks are then used as centers for subsequent drilling operations. 'In the past, such tools have been complex in construction or operation, or in most instances, the machinist or person laying out the holes is required to rely primarily on a plurality of separate tools, such as protractors, scales, straight edges, compasses and the like, and a special degree of skill is required on the part of the user, and substantial time is expended in producing the marks.

Summary of the invention The present invention overcomes the defects of prior arrangements by providing a relatively simple tool which does not require any particular degree of skill in laying out a plurality of circumferentially spaced holes on any predetermined radius. The tool is so designed that once some simple, preliminary settings are made, successive hole locations may be rapidly determined and marked on the work piece with minimum effort on the part of the user. In broad terms, the foregoing is carried out by providing a pair of arms pivotally connected at one end about a common center pin, with each of the arms carrying a longitudinally slidable punch member. As will be later explained in more detail, the arms may be selectively positioned at varying angular dispositions, and since the punch members are likewise capable of radial movement along the arms, a plurality of holes may be punched, or indicia otherwise marked at selective radial and circumferential spacing relative to a center point.

Description of the drawings Description of the preferred embodiment The tool of the present invention, generally designated by the numeral 12 in the drawing is illustrated in ice operative position on a work piece such as the metal plate 13. As will be understood, the tool is adapted to place a plurality of punch holes 14 at some preselected circumferential spacing and at some preselected radial spacing from a center point 16, such a center being illustrated in FIGURE 3 of the drawing.

Briefly, the tool comprises a pair of arms 17 and 18. At adjacent ends of the arms, the arm 17 is provided with a lower generally circular segment 19 which underlies a comparable segment 21 extending from the .arm 18. Each of the arms is likewise notched in an arcuate manner, as indicated at 22, so as to receive the corresponding arcuate segment of the other arm. The segments 19 and 21 are provided with a central bore through which a pin 23 extends, such pin having a pointed bottom end 26 which is adapted to provide the center point 16 of the work piece such as by striking the upper end of the pin with a hammer. The pin may be retained in the segments by providing circumferential grooves on the pin adjacent the upper and lower surfaces of the segments 21 and 19 respectively, with retaining clips 27 disposed in such grooves engageable wtih such surfaces. It will be appreciated that the pointed bottom 26 of the pin 23 may be inserted in a prepunched center hole 16 instead of being used to actually form such center hole.

With the exception of the end segments 19 .and 21 which lie in adjacent horizontal planes and which are complementary to each other, the other portions of the arms are substantially identical, and therefore reference may be had to either one of the arms for a further description thereof. The arrangement of the arms, .and their pivotal connection is such that they may be moved from a first position wherein they are parallel and adjacent to each other to second angular related positions.

As will be noted, each arm has a generally flat upper surface 31 and a comparably flat lower surface 32 with a longitudinally extending slot 33 extending substantially for the length of the arm. A block, generally designated at 36, is mounted on the arm and adapted for longitudinal sliding motion between the ends of the slot 33. In addition to the slot and block arrangement, there is also provided a rod 37 disposed in laterally offset but adjacent relationship to the slot 33 and is positioned above the upper arm surface 31. The block 36 is provided with a horizontal aperture or bore 39 slida-bly receiving the rod and is also provided with a lug 41 extending from the lower surface 42 of the block and engageable with the slot 33 while such lower surface 42 is supported on and engages the upper surface 31 of the .arm.

The block is accordingly capable of sliding longitudinal movement along the arm and is restrained against lateral displacement by means of the lug 41 engaging the sides of the groove 33 and by the engagement of the aperture 39 with the rod 37.

Means are provided for selected positions of axial adjustment along the length of the arm. As here illustrated, a lock block 44 underlies and engages the lower surface 32 of the arm and is provided with a short upwardly extending lug 46 which engages the slot 33. A screw having a manually engageable head 47 extends through the block 36, lug 41, lug 46 and the block 44 in alignment with the slot 33, and by tightening the screw, the blocks are forced together and prevented from further longitudinal movement along the arm. Also, the aperture 39 in which the rod 37 is disposed is provided with a slit 49, and another screw 51 extends through the block on opposite sides of such slit, and upon tightening thereof, prevents movement of the block relative to the rod 37.

It will be noted that one end of the rod extends through a post 53 provided adjacent the pivot end of the arm and the other end of the rod extends through a similar post 54 adjacent the distal end of the arm. This latter end of the rod 37 is threaded as indicated at 56 and a knurled nut 57 is provided which has a cam portion 58 of arcuate shape to engage the outer peripheral portion of the post 54. The end of the rod extending through post 53 terminates in a cap member 59 and a spring 61 is interposed between such cap and the post 53. In this manner, the rod may be moved within small increments of axial adjustment by adjustment of the nut 57, for a purpose to be presently explained. It will be noticed that the block 36 carries a pointed punch 63 which is capable of limited movement in a vertical direction. The punch is restrained from upward removal by means of a clip 64 engageable in a circumferential groove on the punch and which bears against the lower surface 32 of the arm. The punch is slidable vertically in a bore as illustrated in FIGURE 4 provided in the block, such bore being laterally spaced from the lower block 44. The upper end of the punch may be radially enlarged so that it cannot be removed by driving the same downwardly through the block bore. In any event, it will be understood that when the block 36 carrying the punch is positioned at the proper radial spacing from the center point 16, the user may strike the upper end of the punch and thereby mark the work piece at the appropriate radial position. Preparatory to such punching operation, after the block is approximately positioned by manually sliding the same along the arm, the screw 51 is tightened, and nut 57 manipulated to give a fine adjustment to the block location. The screw 47 may then be tightened to prevent further longitudinal movement of the block and the punch carried thereby along the arm.

As previously explained, each of the arms is provided with the above described block and punch arrangement, and in most instances, the radial spacing of each of the blocks from the center 16 will be identical. In other words, if the bolt hole radius is inches, the punches will be set so as to be this predetermined distance of 5 inches from the center pin 23.

If desired, scale indicia 66 indicating such radial dimensions may be provided along the edge of the arm and adapted to be aligned with the side edge of each block.

As an important feature of the present invention, means are also provided for establishing and fixing the predetermined circumferential or arcuate spacing between the punches carried on the respective arms, and consequently of the bolt hole centers marked thereby.

As here illustrated, the arms 17 and 18 are each provided with a vertically extending post 67 and 68 with a horizontal rod extending through the post, or more particularly through apertures provided in such posts, post 68 being rotatably secured to arm 18.

The end of the rod extending through post 67 is threaded and is provided with a bolt 71 adjacent the end of the rod with a spring 72 between the bolt and post. The rod is normally freely movable through the aperture in post 68 so that the arm 18 may be pivoted towards and from the arm 17 with such freedom of motion possible due to the rotation of the post 68 in a bushing 73. The arm 18 may be locked in preselected positions of angular adjustment relative to arm 17 by tightening a screw 74 comprising a foot for the arm 18 which serves to tighten the post 68 against the rod 69 so as to prevent further motion thereof. However, after the pin is tightened so as to provide an approximate arcuate or circumferential spacing, further adjustment of an incremental nature is possible by means of a knurled nut 76 bearing against a washer 77 which in turn moves the rod 69 either with or against pressure of spring 72 for minor adjustment. The post 67 is also provided with a foot screw 78 which forms the foot or support for arm 17.

Just as in the case of the indicia 66, if desired, a protractor could be incorporated to measure the angular inclination of the arms as they are selectively adjusted.

With the foregoing description, it will be understood that the blocks are thuscapable of accurate positioning in both radial and circumferential positions of adjustment, and once such adjustment is made, the entire tool may be rotated about the pin 23 in its center hole 16 with the punch members carried on the respective blocks sequentially placed in one location after the other and successive punches made until the required number of holes or indicia has been marked on the work piece. It will also be appreciated that the tool may be used 1n other manners and for other purposes than that above described. By Way of example, the pins 23 and 63 may be placed against a straight edge and pins 63 punched. The tool may be moved along such straight edge and another pair of spaced pairs of punch marks may be marked at selective lineal distances from each other.

What is claimed is:

1. A tool of the character described comprising a pair of arms, means pivotally connecting adjacent end portions of said arms together whereby said arms may be moved between a first position wherein said arms are disposed in substantially parallel adjacent relation and a plurality of other positions wherein said arms are disposed at selective angular dispositions, a block member slidably mounted on each arm, a punch carried by and depending from each block member, means releasably clamping each block member to its respective arm in selected positions of adjustment, a horizontally extending rod carried by each arm in parallel relationship therewith, means releasably clamping each block member to its respective rod, and means for incrementally moving each rod and the block clamped thereto relative to its respective arm when said block member clamping means is released.

2. A tool as set forth in claim 1 in which the distal end portions of said arms are provided with posts, a traversing rod mounted in said posts and interconnecting said end portions, andmeans for releasably locking said traversing rod in said posts.

3. A tool as set forth in claim 2 in which one of said posts is rotatably carried on its arm and is provided with a horizontal aperture-for receiving said traversing rod.

4. A tool as set forth in claim 2 including means for incrementally moving said traversing rod when in its locked position for incrementally varying the angular dispositions of said arms.

5. A tool as set forth in claim 1 in which each arm is provided with a longitudinal slot with portions of said block extending through said slot, and each block having an aperture for receiving its respective rod in sliding engagement therewith.

References Cited UNITED STATES PATENTS 1,566,509 12/ 1925 Schwanz 33-189 2,772,482 12/ 1956 Downs 33-150 3,105,305 10/1963 Ditfee 33-189 2,928,178 3/1960 Wilcox 33189 FOREIGN PATENTS 84,778 8/ 1920 Switzerland. 103,699 7/1926 Austria.

WILLIAM D. MARTIN, 111., Primary Examiner US. Cl. X.R. 33-27, 149 

